1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#pragma once
#include <set>
#include <vector>
#include "mongo/db/exec/plan_stage.h"
#include "mongo/db/exec/sort_executor.h"
#include "mongo/db/exec/sort_key_comparator.h"
#include "mongo/db/exec/sort_key_generator.h"
#include "mongo/db/exec/working_set.h"
#include "mongo/db/record_id.h"
namespace mongo {
/**
* Sorts the input received from the child according to the sort pattern provided.
*
* Preconditions:
* -- For each field in 'pattern', all inputs in the child must handle a getFieldDotted for that
* field.
* -- All WSMs produced by the child stage must have the sort key available as WSM computed data.
*/
class SortStage final : public PlanStage {
public:
static constexpr StringData kStageType = "SORT"_sd;
SortStage(boost::intrusive_ptr<ExpressionContext> expCtx,
WorkingSet* ws,
SortPattern sortPattern,
uint64_t limit,
uint64_t maxMemoryUsageBytes,
std::unique_ptr<PlanStage> child);
bool isEOF() final {
return _sortExecutor.isEOF();
}
StageState doWork(WorkingSetID* out) final;
StageType stageType() const final {
return STAGE_SORT;
}
std::unique_ptr<PlanStageStats> getStats();
/**
* Returns nullptr. Stats related to sort execution must be extracted with 'getStats()', since
* they are retrieved on demand from the underlying sort execution machinery.
*/
const SpecificStats* getSpecificStats() const final {
return nullptr;
}
private:
// Not owned by us.
WorkingSet* _ws;
SortExecutor _sortExecutor;
SortStats _specificStats;
// Whether or not we have finished loading data into '_sortExecutor'.
bool _populated = false;
};
} // namespace mongo
|
